Queensland is suffering a disaster "of biblical proportions" that will set back its economic recovery, state Treasurer Andrew Fraser says.

Rockhampton's airport is closing to commercial flights this afternoon as floodwaters take hold in the Queensland town.

Queensland's flood crisis has affected 200,000 people over an area bigger than France and Germany combined.

Two aftershocks have struck 20km west of Christchurch this morning, GNS Science is reporting.

Christchurch's Boxing Day aftershocks and the recent wet weather have seen more than 1000 claims lodged with the Earthquake Commission.

Tomorrow night's New Year's Eve celebrations in Cathedral Square will go ahead as planned, after quake-hit buildings were deemed safe.

The southeast Queensland city is braced for its highest flood peak in 50 years, with 200 people already evacuating their homes.

Entire Queensland towns have been inundated and more could go under in a deluge that's swamped the state makes its way towards the sea.

Mass evacuations are under way across flooded Queensland with disasters declared in the inland towns of Theodore, Dalby and Chinchilla.

Residents in the street worst affected by September's earthquake may spend another two Christmases waiting for their homes to be rebuilt.

The head of AMI Insurance, the largest New Zealand-owned insurer operating here, says the firm is on sound footing, three months after the Canterbury earthquake.

Canterbury's massive earthquake and aftershocks are likely to rank as the fifth most costly quake ever for insurers.